1. Field of the Invention
The present invention is generally related to a water injection system for an internal combustion engine and, more specifically, to a system for drawing water from a body of water in which a marine vessel is operated and conducting that water to at least one combustion chamber of an internal combustion engine that is used in the marine propulsion system of the marine vessel.
2. Description of the Prior Art
It is well known that certain advantages can be obtained in the operation of an internal combustion engine if water is injected either directly into a combustion chamber or into the air stream flowing toward the combustion chamber.
U.S. Pat. No. 5,937,799, which issued to Binion on Aug. 17, 1999, discloses a cylinder water injection engine. It is described as an environmentally accommodating, reduced NOx, spark or plasma ignited, reciprocating, multi-fuel engine utilizing direct, in-cylinder water injection and an optional oxygen enriched air supply. The engine is also described as being able to operate as an ultra-lean burn, high compression ratio engine for notable power output and increased efficiency. The in-cylinder low-temperature water injection promotes numerous desirable effects. For example, it significantly lowers compression temperatures through the latent heat of vaporization of the water, the lower temperature of compression permits increased compression ratios while avoiding pre-ignition, and the water injected air/fuel demands less work in the compression stroke. As a result, it increases overall engine efficiency. The system also promotes increased mass flow through the engine for increased power output and efficiency and, furthermore, it lowers the formation of nitrogen oxide emissions.
U.S. Pat. No. 4,448,153, which issued to Miller on May 15, 1984, describes a water injection system for a combustion engine. The engine is described as having an intake manifold and carburetor to which water is injected or sprayed by an electrically powered pump receiving water from a reservoir. Switches responsive to engine temperature, engine oil pressure, and engine intake manifold vacuum are used to determine whether the circuitry for energizing the pump will be opened or closed. A valve member that is responsive to the intake manifold vacuum serves to permit a greater rate of flow of the water to the engine upon the manifold vacuum decreasing to a predetermined magnitude.
U.S. Pat. No. 4,096,829, which issued to Spears on Jun. 27, 1978, describes a water injection system for an internal combustion engine. The liquid injection apparatus is used with an internal combustion engine which has an ignition system. It comprises a liquid pump and an electrical drive therefore. The pump has an outlet which communicates with the engine air intake. A control means includes a pulse rate frequency to analog converter to control electrical current flow to the drive in response to and as a function of electrical pulses produced by the ignition system. As a result, the flow of liquid of the engine air intake is a function of the pulse output of the ignition system.
U.S. Pat. No. 4,351,289, which issued to Renda on Sep. 28, 1982, describes a water injection system for an internal combustion engine. The water injection is carried out in a pressure system, with water from a reservoir pressurized by an injection pump energized only above predetermined torque demand levels and under a control of a vacuum switch sensing intake manifold pressure. The injection of water is also precluded until the engine reaches operating temperature by a vacuum switch connected to a PVS valve. A water spray nozzle is mounted in the air cleaner and directs droplets into the carburetor intake. A purging pump causes purging of a short section of the feed line upstream of the injection nozzle after the engine is shut off in order to minimize water drippage into the engine carburetor.
U.S. Pat. No. 4,300,483, which issued to Goodman on Nov. 17, 1981, describes an electronically controlled fluid injection system for an internal combustion engine. The system is intended for use with an internal combustion engine in which an injection nozzle injects a finely divided spray of fluid, such as water or a water solution, into the engine in response to a flow of atomizing air. The nozzle is connected to a fluid supply reservoir and to the outlet line of an air injection pump connected to the intake manifold of the engine and to an electronic circuit that includes an inductive pick-up coupled to the ignition system of the engine. The pump operates in response to engine speed by virtue of its connection to the ignition system and in response to engine load by virtue of its connection to the intake manifold. As a result, the flow of atomizing air to the nozzle and therefore the rate and magnitude of water injection is responsive to engine speed and engine load.
U.S. Pat. No. 4,448,179, which issued to O'Hara on May 15, 1984, describes a water injection system for an internal combustion engine. The system controls the amounts of water injected into the fuel intake to the cylinders in proportional response to the pressure in the engine's exhaust manifold. First conduit means, preferably including an extended surface heat sink and a length of flexible, plastic tubing, communicate the exhaust manifold pressure to the upper surface of a supply of water in an enclosed container. A lower part of the container is connected by second conduit means to a point in the fuel intake system, preferably in the air inlet to the carburetor. An adjustable throttling valve is interposed in the second conduit means for selective control of the relation of water flow to exhaust manifold pressure.
U.S. Pat. No. 4,240,380, which issued to Slagle on Dec. 23, 1980, describes a water injection system. Water is pumped from a holding tank through nozzle means to an area above the carburetion means on an internal combustion engine. The pumping means is controlled by diaphragm means reacting to intake manifold pressure as well as manual control. Filtering means are provided to allow the use of normal tap water. The diaphragm control means operates only after intake manifold pressure has risen to a certain point and ceases to operate after it has risen above a second point of pressure. In another version, a variable pump is used to provide water in direct relationship to the manifold pressure over the indicated or selected range. The nozzle and the carburetion means act together to provide proper atomization of the water in the fuel air mixture.
U.S. Pat. No. 3,894,166, which issued to Brown et al on Jul. 8, 1975, describes an integral reverse osmosis membrane with a highly pressed woven fabric support member. The integral cellulosic reverse osmosis membrane has a permeable fabric support and is made by a process which comprises casting a concentrated membrane-forming dope and forming a reverse osmosis membrane on a smooth surface of a permeable casting and membrane support fabric comprising substantially unsized continuous multiple warp and fill strands of fiber-forming crystalline organic thermoplastic resin, which fabric has been highly pressed at temperatures and pressures sufficient to smooth the surfaces of the fabric to a high degree of smoothness and sufficient to substantially completely close permanently the interstices at the strand intersections while leaving the pressed fabric permeable to the flow of a fluid such as desalinated water.
U.S. Pat. No. 4,770,775, which issued to Lopez on Sep. 13, 1988, describes an apparatus for the production of fresh water from sea water by reverse osmosis. The invention relates to an apparatus for the production of fresh water from seawater, intended to be immersed into the marine medium. The apparatus comprises one high pressure chamber containing a selective semi-permeable reverse osmosis membrane and a bell chamber having an internal axial piston permitting by a multiplier effect, to obtain at the interior of the chamber a pressure equal to the exterior pressure multiplied by a ratio S/s of the working surfaces of the bell chamber and the internal piston. The semi-permeable membrane communicates across a separation wall of the high pressure chamber with the interior volume of the bell chamber. This internal volume is placed in communication with the surface by a flexible tube in such a manner as to play the dual role of, on one hand, a subatmospheric gas chamber, and on the other hand means for receiving fresh water after osmosis across the membrane.
U.S. Pat. No. 4,846,970, which issued to Bertelsen et al on Jul. 11, 1989, describes a cross-flow filtration membrane test unit. A cross-flow filtration membrane test unit has a bottom cell body, a top cell body, and a pair of laterally spaced O-rings forming a seal therebetween. The bottom cell body is provided with a feed spacer cavity and the top cell body is provided with a permeate carrier cavity. A mechanism for receiving a test sample of membrane enables the membrane performance and characteristics to be tested in a manner which closely simulates actual full-scale operation.
U.S. Pat. No. 4,741,823, which issued to Olsen et al on May 3, 1988, describes a flow control manifold for cross-flow membrane systems. A cross-flow membrane system is described for separating feed water into a concentrate stream and a permeate stream which includes a cross-flow membrane module, a pump for pressurizing feed water for supply to the module and a flow control manifold block having a permeate, a concentrate bore, and a concentrate orifice for controlling the flow of concentrate from the system and the operating pressure within the cross-flow membrane module. The manifold block simplifies the manufacture, operation and maintenance of the system and allows an elimination of many of the tubes, hoses, and valves which are commonly required in prior art systems.
U.S. Pat. No. 5,744,008, which issued to Craven on Apr. 28, 1998, describes hurricane tower water desalination device. A simple, portable, and efficient water desalination device uses deep ocean water, solar energy, and the dynamics of generated secondary vortices to operate. The device includes a tower, a heat exchanger positioned inside the tower near the top of the tower, a cold water source, a cold water receiving tank, a condensate catchment grille, a freshwater collecting tank, a rotor extending upward between the side walls of the tower from a lower portion of the tower, a power source for driving the rotor, a warm salt water pan positioned in the bottom of the tower and a warm salt water source. The cold water source is cold deep ocean water that is siphoned to the top of the tower through rollable, transportable fabric pipes. The warm salt water source is solar heated ocean water. In the water, a hurricane is simulated by a rotating column that induces a circulation of air which approximates that of a hurricane. The rising warm vapor contacts the cold plate of the heat exchanger, condenses into droplets on the plate, and collects in a reservoir. That process is accomplished without consuming ocean water nutrients. Multiple desalination devices are placed on a barge to create a mobile vortex-principal desalination plant for military operations and other temporary or emergency applications.
The patents described above are hereby explicitly incorporated by reference in the description of the present invention.
A "Pure Water Handbook" which is published by Osmonics, Inc., describes the basic elements of water purification. It also discusses various types of impurity and methods of water purification. These methods include reverse osmosis, nanofiltration, and ultrafiltration. Water filtration systems are available in commercial quantities from the Osmonics Corporation which makes various types of desalination systems and components thereof. In addition, PUR water makers are available in commercial quantities from Recovery Engineering, Inc. and these systems are suitable for providing fresh water for use on marine vessels.
Although water injection has been used in conjunction with internal combustion engines to improve the operation of the internal combustion engines, all known systems have required the use of a reservoir in which clean water is contained and used for the purpose of injection into the combustion chamber of an engine or into the air stream flowing to the combustion chamber. The requirement of a water reservoir necessitates the refilling of the reservoir as the water is consumed for its intended purposes. This requirement of a water reservoir has severely limited the application of water injection systems for internal combustion engines.
Internal combustion engines used in marine propulsion systems are uniquely suited for water injection into the combustion chambers of internal combustion engines if the surrounding water, in which the marine vessel is operated, can be used for these purposes. Heretofore, the silt, sediment, salt, and other debris suspended in the body of water prohibited its use for these purposes. It would therefore be significantly beneficial if a means could be developed in which water can be drawn from a body of water in which a marine vessel operates and then used in a water injection system of the internal combustion engine.